A technology of operating a safety apparatus before colliding with an obstacle in a case where a distance from the obstacle is very narrow while driving a vehicle, such that the collision is not avoidable, thereby minimizing damage to the vehicle and protecting a passenger as safe as possible after the collision has been developed. An example of the safety apparatus includes an active bumper apparatus, a bumper air bag apparatus, or the like.
An example of an impact absorbing apparatus according to the related art is shown in FIG. 1. The impact absorbing apparatus shown in FIG. 1 is configured to include a motor 3 installed to be fixed to a bumper 1 through a bumper bracket 2, a lead screw 4 receiving power from the motor 3 to thereby be shaft-rotated and having one end coupled to the bumper bracket 2, a fixing nut 6 screwed to the lead screw 4 and installed to be fixed to a vehicle body frame 5 spaced apart from the bumper bracket 2, and a length variable energy absorbing shaft 7 disposed in parallel with the lead screw 4 and having one end fixed to the bumper bracket 2 and the other end installed to be fixed to the fixing nut 6.
In the impact absorbing apparatus according to the related art, when the motor 3 is driven, the power of the motor 3 is transferred to the lead screw 4 through a gear 8, such that the lead screw 4 is rotated. In this case, the fixing nut 6 is fixed to the vehicle body frame 5, such that the lead screw 4 is moved forward of the vehicle simultaneously being rotated. Therefore, the bumper 1 is moved and protruded forward of the vehicle, and the energy absorbing shaft 7 performs an operation of increasing its length.
Therefore, an obstacle positioned in front of the vehicle does not directly collide with a vehicle body, but collides with the bumper 1 protruded forward, such that damage to the vehicle may be decreased and a passenger may be safely protected after collision.
However, since the impact absorbing apparatus according to the related art as described above has a structure installed within a lower space of a back beam of a bumper, the lower space of the back beam may not be utilized. In addition, since the impact absorbing apparatus according to the related art as described above uses the motor 3 as a power source and uses the lead screw 4 in order to transfer the power, the structure thereof is complicated and weight thereof is heavy. Particularly, a system configuration thereof is complicated, such that excessive cost is required at the time of repair, and responsiveness is low until the bumper 1 is protruded due to the structure in which the bumper 1 is protruded by the rotation of the lead screw 4.
Further, since the impact absorbing apparatus according to the related art as described above has the structure in which the bumper 1 absorbs impact while being protruded, a secondary impact may be applied to the pedestrian by protrusion force of the bumper 1 at the time of collision with the pedestrian. Therefore, there is a risk that injury to the pedestrian will increase.
The matters described as the related art have been provided only for assisting in the understanding for the background of the present disclosure and should not be considered as corresponding to the related art known to those skilled in the art.
KR 10-1998-0060942 A has proposed such a bumper impact absorption device of a vehicle.